Makoto is a nice and considerate guy, who is always concerned about his friends' welfare. Due to his caring personality, he is often seen with a gentle smile on his face.However, he is rather weak-hearted and can get scared easily, as shown when he appeared terrified of the possibility that their old Swimming Club may be haunted. When he gets scared he tends to hide behind Haruka or cling to him in some way.

Makoto also seems to be one of the more sensible people in the group and can get a bit worn out from his friends' peculiar antics and mannerisms. He is the one usually restraining Haruka from randomly stripping or diving into fish tanks.

Makoto and Haruka have been together for so long that Makoto is able to read Haru's mind. He is also shown to be slightly manipulative, often using Haruka's love of water to his advantage to convince Haru to do what he wants. It was also shown that Haruka dislikes it when people use his first name, but Makoto always somehow manages to win the argument and call him 'Haru'.